5th lecture - hypnotics & sedatives Flashcards
(78 cards)
define neuroleptic
(of a drug) tending to reduce nervous tension by depressing nerve functions; are both tranquillizers & antipschyotics.
function of the Cerebral cortex
consciousness, memory, thought (cortical functions)
function of the brain Centres in the subcortical regions
emotions, moods, experiences/perception (subcortical functions)
psychosedative effect =
Depression of cortical brain function
psychostimulation =
Stimulation of cortical brain function
euphoric, psychostimulatory drugs have what type of effects
Psychological stimulation
Neurosis means
a neurotic disorder, irritability or other such effects resulting from psychological overload.
involves symptoms of stress (depression, anxiety, obsessive behaviour, hypochondria) but not a radical loss of touch with reality.
In veterinary medicine neuroleptics and tranquilizers are described as one group of drugs, called:
major tranquilizers.
antipsychotics/anti-hallucinogenics are also known as
neuroleptics
overall depressant effect on the CNS
some subgroups of neuroleptics include: (4)
Phenothiazines (e.g. Plegicil/ace)
Thioxanthenes
Butyrophenones
Indoles (e.g. ondis and tadalafil)
Example of a common phenothiazine used in vet med
acepromazine (Plegicil)
example of a butyrophenone
(neuroleptic subgroup)
azaperone is used in vet med
example of an indole
(neuroleptic subgroup)
reserpine
neuroleptics pharmacokinetics (3)
Absorption is good,
they penetrate the blood-brain barrier, metabolism occurs in the liver.
neuroleptics mechniams of action
They suppress all mediatory systems in the brain and in the periphery:
adrenergic,
cholinergic,
histaminergic ,
serotonergic,
and dopaminoreactive systems.
The main effect and also secondary effects of neuroleptics are primarily related to the
dopamine blocking effect as the dopaminergic transmission in the central nervous system is blocked.
pathway from Tyrosine to Noradrenaline
Tyrosine, L-DOPA, Dopamine, Noradrenaline
Dopamine is a mediator with a catecholamine structure, mainly functioning in the brain structures related to
regulation of the psyche/ psychological domain: striatum, hypothalamus, hippocampus, mesolimbic structures and the fourth ventricle.
name dopamine receptors
5 subtypes are distinguished.
Pharmacologically important D1, D2 and D3.
The effect of neuroleptics is realised through D2 receptors.
Dopamine is broken down by
MAO and COMT.
monoamine oxidase
catechol O methyltransferase
neuroleptic antipshyotic effect is due to the blocking of what?
Antipsychotic effect due to dopamine blocking effect, limbic and cortical dopaminergic transmissions are blocked.
neuroleptic sedative effect is due to the blocking of what?
Sedative due to cholino and histamine blocking effect.
Cardiovascular effects of neuroleptics
Blockade of the central and peripheral effects of catecholamines:
Alfa-blockade = eripheral vasodilation
Arterial hypotension, even up to shocklike conditions especially in compromised patients.
define intrathecal
introduced into or occurring in the space under the arachnoid membrane of the brain or spinal cord.